摘要
虽小浪底水库已建成投入运用 ,四次加高了黄河下游的大堤 ,但黄河下游的防洪形势依然严峻。自195 8年以来 ,在黄河下游的河滩上修筑了生产堤。生产堤的总长达 6 0 0km ,围去了 80 %的行洪滩地面积。由于生产堤的修建 ,大多数的洪水都被限在生产堤间行洪 ,只有两生产堤间的滩地可以上水和泥沙淤积。大堤和生产堤间的滩地没有行洪和泥沙淤积的机会。因此 ,生产堤间的主槽和滩地要比生产堤与大堤间的滩地要高得多。这就形成黄河下游的二级悬河。在主槽滩唇和近大堤的低滩之间形成很大的横比降。这就威胁到大堤的安全。有破坏性的横河、斜河可以发生 ,一旦遇较大洪水就要溢出生产堤并直冲大堤根部。上游水库的调节运用不可能阻止二级悬河的形成和发展 ,情况将进一步恶化。为了保障黄河下游大堤的防洪安全 ,作者提出了以下几点建议 :( 1)拆除生产堤 ,恢复滩地的行洪沉沙作用 ;( 2 )利用泥沙加宽和加固大堤 ,淤筑相对地下河 ;( 3)进行主河槽疏浚并将泥沙淤在生产堤和大堤之间 ,减小主槽和大堤根的横向高差 ;( 4 )将滩地的居民迁移至加宽了的大堤上居住 ,给他们解决去滩地耕种的道路和交通问题 ;( 5 )疏浚并整治主河槽 ,中水河槽的整治流量可以按 30 0 0～ 4 0 0 0m3/s ,河道整治工程控导河势 ,但要允许洪水漫?
Since 1958, farming levees have been built in the floodplain between the major levees at the lower Yellow River. The farming levees have a total length of about 600km, enclosing almost 80% of the floodplain area. As a result of the construction of these farming levees, most floods with mid level discharge have been confined inside these levees.Consequently, only floodplain between the farming levees could be inundated, and sediment could only be deposited in this area, not the area of floodplain between the farming levees and the major levees. This caused the higher elevation of the main channel and floodplain between the farming levees than that of the floodplain outside the farming levees, and thus the secondary suspended river is formed(the Yellow River at the lower reaches is a suspended river itself relative to the land it flows through). Inside the major levees,the very large lateral slope caused by elevated main channel and relatively low floodplain near the major levees is of grave concern to the safety of the major levees, as small but damaging lateral flows may occur and scour the foot of the major levees once the heavy flood is overflowing the confinement of the farming levees. It is found that the operation of upstream reservoirs could not stop the forming of the secondary suspended river. On the contrary, the situation will be worse with time. To improve the flood control capacity and safety of the major levees of the lower Yellow River, the authors made the following suggestions: (1) abolish the farming levees, and restore the floodplain’s flood conveying and sediment depositing functionality; (2) using deposited sediment to widen and strengthen the major levees and construct relative non suspended river; (3) conduct dredging of main channel and deposit sediment between the farming levees and the major levees, and thus reduce the lateral elevation difference between the main channel and the foot of the major levees; (4) relocate the floodplain residing people to behind the widened major levees, while providing them easy access to their farming land in the floodplain; and (5) the dredging and channel regulation should be guided by a bankfull discharge of 3000-4000 m\+3/s; the regulation should aim at controlling channel regime under mid level magnitude floods, and overbank flows should be allowed.
出处
《泥沙研究》
CSCD
北大核心
2004年第2期1-4,共4页
Journal of Sediment Research
关键词
小浪底水库
黄河
泥沙
河道整治
生产堤
防洪:
secondary suspended river
sediment
river regulation
flood control
the Yellow River
farming levee
